diff --git a/man2/statx.2 b/man2/statx.2 index 4a4d30251..9148fbbb0 100644 --- a/man2/statx.2 +++ b/man2/statx.2 @@ -463,26 +463,26 @@ It cannot be written to, and all reads from it will be verified against a cryptographic hash that covers the entire file (e.g., via a Merkle tree). .TP -.BR STATX_ATTR_DAX (since Linux 5.8) +.BR STATX_ATTR_DAX " (since Linux 5.8)" The file is in the DAX (cpu direct access) state. DAX state attempts to minimize software cache effects for both I/O and memory mappings of this file. It requires a file system which has been configured to support DAX. -.PP +.IP DAX generally assumes all accesses are via CPU load / store instructions which can minimize overhead for small accesses, but may adversely affect CPU utilization for large transfers. -.PP +.IP File I/O is done directly to/from user-space buffers and memory mapped I/O may be performed with direct memory mappings that bypass the kernel page cache. -.PP +.IP While the DAX property tends to result in data being transferred synchronously, it does not give the same guarantees as the .B O_SYNC flag (see .BR open (2)), where data and the necessary metadata are transferred together. -.PP +.IP A DAX file may support being mapped with the .B MAP_SYNC flag, which enables a